1. Field of Invention
The invention relates to a winding device for winding up a web-like material as described herein.
2. Description of the Prior Art
Web-like material, such as plastic film, which is produced in a web production device, such as an extrusion device, is frequently not processed further directly, i.e., “in-line”, but rather first wound up into rolls using a so-called winding device. These rolls are first supplied to a further processing machine. Such further processing machines include printing presses, bag production machines, and many other machines.
Other materials, such as paper, are also wound up in a winding device and supplied to a further processing machine in the form of rolls.
These rolls are frequently formed in that the web-like material is wound onto a roll core. Before the web-like material reaches this roll core and/or the roll, on which web-like material is already wound, it is guided over a web guiding roller. This web guiding roller may be situated at a small distance to the roll core or to the roll (so-called “gap winder”) or may press the web-like material directly onto the roll core or the roll. In the latter case, the winding device is referred to as a contact winder. In both cases, the cited web guiding roller is typically the last roller over which the web-like material is guided before or when it reaches the roll core or the roll.
To prevent an air inclusion between the roll core or the roll and the new layer of the web-like material, a pressing element is frequently assigned to the roll, which may be positioned against the roll. This pressing element is typically designed as a pressing roller.
In known winding devices, the mechanism which is used for positioning the pressing elements on the roll, comprises carriages, in which the pressing roller or the pressing element is mounted on both ends, the carriages being situated so they are displaceable on two rails running parallel to one another. These rails are fastened to walls which also support the roll core. The carriages on which the pressing rollers are mounted are moved in the direction toward or away from the roll core using suitable actuators, such as a piston-cylinder unit.
This way of positioning the pressing roller on the roll core has the disadvantage of the large space requirement caused by a linear guide of the carriages.
The object of the present invention is to propose a winding device, in which the mechanism which is used for positioning the pressing element on the roll requires less space.
The object is achieved by a winding device as described herein.